POEM gives scientists a chance to conduct microgravity experiments in space for up to three months. Normally, the empty stage of the rocket would just become space debris after launching the main payload.
The PS4-Orbital Experiment Module, known as POEM, uses the empty fourth stage of the Polar Synchronous Launch Vehicle (PSLV) for experiments in space. This setup allows scientists to conduct various tests and research in orbit.
POEM gives scientists a chance to conduct microgravity experiments in space for up to three months. Normally, the empty stage of the rocket would just become space debris after launching the main payload. Instead, POEM allows researchers to make use of it for valuable experiments.
These experimental payloads help test new ideas and technologies that could be important for future space missions.
PSLV-C60 SpaDeX: POEM-4 Mission Overview
The PSLV-C60 SpaDeX mission is the fourth mission in the POEM series, known as POEM-4. This mission aims to achieve specific objectives related to space exploration and technology.
The PSLV-C60 SpaDeX mission includes two small spacecraft, called ‘Chaser’ and ‘Target,’ each weighing about 220 kg. The mission aims to demonstrate space docking technologies. Both spacecraft will be launched independently and simultaneously by the PSLV-C60 rocket into a circular orbit at 470 km altitude and a 55° inclination, with a local time cycle of about 66 days. The launch is planned for the end of the year.
The POEM-4 mission will carry a total of 24 payloads. Of these, 14 are from ISRO and its centers, while 10 are from various non-government entities (NGEs), including universities and startups, which were selected through IN-SPACe.
This mission marks a major improvement, with the capacity of POEM increasing three times compared to the previous POEM-3 platform, which only carried eight payloads.
A.The POEM-4 mission by ISRO carries 14 cutting-edge payloads developed by its centers. These include 5 from Vikram Sarabhai Space Centre (VSSC), 4 from the Space Physics Laboratory (SPL) at VSSC, 3 from the ISRO Inertial Systems Unit (IISU), 1 collaborative payload from SPL and IISU, and 1 from the Indian Institute of Space Science and Technology (IIST). The payloads are:
I. RRM-TD: Walking Robotic Arm – A robotic arm that can perform tasks in space like walking on surfaces, repairing satellites, and supporting space station development.
II.Debris Capture Robotic Manipulator – A robot designed to capture and remove dangerous space debris, keeping space safe and clean.
III. Reaction Wheel Assembly (RWA) – A system that helps spacecraft rotate and stay oriented accurately during their missions.
IV.Multi-Sensor Inertial Reference System (MIRS) – A navigation tool that uses multiple sensors to ensure spacecraft move and remain stable in space.
V.Lead Exempt Experimental System (LEXS) – Tests environmentally friendly, lead-free electronics in space for future sustainable technologies.
VI. MEMS-based Rate Sensor – A sensor that measures fast movements of spacecraft during critical mission phases like launch and re-entry.
VII. Payload Common Onboard Computer (P-COC) – A computer that manages and controls scientific experiments conducted in space.
VIII. Electron Temperature Analyser (ETA)– Measures the temperature of electrons in Earth’s ionosphere to study space weather and atmospheric changes.
IX. Electron Density and Neutral Wind (ENWi) – Studies how charged particles and winds in space affect the ionosphere, which impacts communication and GPS systems.
X. Langmuir Probe (LP) – Examines properties of charged particles in the ionosphere, such as their temperature and density.
XI. Ionosphere TEC Measurement using NavIC (PLASDEM) – Uses India’s NavIC satellite system to study delays caused by charged particles in the ionosphere, improving navigation accuracy.
XII. Laser Firing Unit (LFU) and Laser Initiation Pyro Unit (LIP) – Tests the use of lasers to safely ignite spacecraft thrusters instead of traditional electrical systems.
XIII. Compact Research Module for Orbital Plant Studies (CROPS) – Tests how plants grow in space by germinating cowpea seeds to study food production in microgravity.
XIV. PILOT-G2 (GRACE) – Tests advanced technologies for small satellites and measures harmful space radiation that can affect electronics and astronauts.
These payloads demonstrate ISRO’s focus on space robotics, sustainability, navigation, ionospheric studies, and futuristic technologies.
B. 10 Payloads from Non-Governmental Entities (NGEs) and Start-ups
1. Amity Plant Experimental Module in Space (APEMS) : The APEMS payload, developed by Amity University, Mumbai, studies how plant cells (using spinach) grow and adapt in microgravity compared to Earth. It uses LEDs for light, a gel for nutrients, and cameras to monitor growth. This experiment helps understand plant growth in space, essential for future space missions.
2. BGS ARPIT (Amateur Radio Payload for Information Transmission) : The BGS ARPIT payload, developed by SJC Institute of Technology,Chikkaballapur Karnataka operates under the guidance of Adichunchanagiri Math , transmits audio, text, and images via satellite using FM and VHF. It promotes global amateur radio services and supports educational outreach in India’s space sector.
3. RVSat-1 : The RVSat-1 payload, developed by RV College of Engineering, Bengaluru, studies the growth of gut bacteria in space with prebiotics. This helps understand astronaut health and supports advancements in antibiotics, waste recycling, and space exploration.
4. Green Propulsion: RUDRA 1.0 HPGP :
The RUDRA 1.0 HPGP payload, developed by Bellatrix Aerospace, Bengaluru, demonstrates a compact green propulsion system for satellites. It tests steady thruster firing, thermal stability, and advanced in-house propulsion technologies for space applications.
5. Green Propulsion Thruster: VYOM-2U : The VYOM-2U payload, developed by Manastu Space Technologies, Mumbai, demonstrates a safer hydrogen peroxide-based thruster for satellites, offering improved performance over hydrazine with high thrust, efficiency, and long continuous firing capability.
6. SAR Imaging Demonstration Payload (GLX-SQ): The GLX-SQ payload, developed by GalaxEye Space Solutions, Bengaluru, demonstrates SAR (Synthetic Aperture Radar) image processing in space, compressing 400 MB to 1.5 MB in under 10 minutes, advancing remote sensing for future SAR + EO (Earth Observation) missions.
7. Varuna : The Varuna payload, developed by Piersight Space, Ahmedabad, demonstrates a CubeSat Synthetic Aperture Radar (SAR) with advanced subsystems, testing reflectarray antenna, SAR components, and X-Band radio, paving the way for SAR + AIS (Automatic Identification System) satellite constellations.
8. Swetchasat : The Swetchasat payload, developed by Nspace Tech, Andhra Pradesh, demonstrates a UHF transmitter for reliable communication with ISRO ground stations, collects environmental and ionospheric data, and supports telemetry downlink, designed for advanced space missions.
9. MEMS-based Inertial Measurement Unit: STeRG-P1.0 : The STeRG-P1.0 payload, developed by MIT WPU, Pune, tests small sensors and processors to measure movement and orientation in space, using advanced data filtering and storage techniques for accurate and efficient performance.
10. MOI-TD : The MOI-TD payload, developed by TakeMe2Space, Hyderabad, demonstrates an AI lab in space, processing Earth observation data in real time, testing subsystems, and using AI to capture and analyze sharp Earth images.
